James 2:18

James 2:18 says, Yea, a man may say, Thou hast faith, and I have works: shew me thy faith without thy works, and I will shew thee my faith by my works.  James said that some might say that they had faith and another person had works to redeem them, but that faith could not be shown without works, or actions that proved one's faith.  Our works do not save us, faith in Jesus Christ does, but our works show our faith ti the world.  

Verse nineteen adds, Thou believest that there is one God; thou doest well: the devils also believe, and tremble.  James said that if we believe that there is but one God, we do well, but that demons also believe this. Many religions believe that there is but one god, just not the One God.  

Verse twenty continues, But wilt thou know, O vain man, that faith without works is dead?  James said we were vain, or foolish, if we claim we have faith, but it doesn't lead us to doing anything for God.  Our faith in Jesus Christ should lead us to do the work that He calls us to do.